It's when bunch of people on the internet decide to try to convince people that doing something ridiculous will get them high.
A while ago they did the same thing with putting toothpaste on your nipples.
The difference this time is that this might be genuinely dangerous (haven't been bothered to look into the chemistry of it).

any time friend, basically it just fries your brain(not in the stoner sense as in the literal chemicals cook your brain) and that feeling isnt known by the brain so it releases endorphins in a lolidontknowwhattodo state and thats the feeling you get, similar to the one you get working out